Ruler.



Patented July 30, 1918.

lllLlllLllllllL C. H. LITTLE.

RULER.

APPLICATION HLED MAY 26. 1913.

fig]. 1. rT ll m IHIHHH j6ll 1 a llllllllfMHFF UNITED STATES PATENT OFFICE.

CHARLES H. LITTLE, OF EAST CLEVELAND, OHIO.

RULER.

Application filed May 26, 1913.

To all whom it may concern:

Be it known that I, CHARLES H. LI'JITL'E, a citizen of the United States, residing at East Cleveland, in the county of Guyahoga and State of Ohio, have invented a certain new and useful Improvement in Rulers, of which the following is a full, clear, and exact description.

This invention relates to improvements in rulers, such as forms the subject matter of my prior application for rulers, Serial No. 652,918, October 5th, 1911, the present invention being in the nature of an improvement over certain features embodied in the ruler construction disclosed in said application.

The ruler constructed in accordance with my prior invention comprises a body which is formed into tubular shape from a thin strip of sheet metal. This body, unlike the body of a wooden ruler, will not warp out of shape, but at the same time, it is light in weight, possesses rigidity and stiffness, and has edges which are straight and parallel, and which in the case of the scale are thin, as is desirable for close accurate work. In addition to the above mentioned important features, the ruler is provided along its edges with a strongly adhering medium, in the form of strips, which are cemented to the body, and in which graduations and characters may be cut.

The present invention in one of its aspects resides in certain improvements in the construction of the ruler body, one of the objects being to provide more effective means for preventing lateral springing or spreading of the ruler body, and distortion of the side edges from true parallelism. Another object is to provide a closure for the ends of the tubular ruler body which does away with the necessity for closing inserts and which provides a strong, neat and otherwise desirable end construction.

A further object is to provide an improvement in the medium which is applied to the ruler body, for the cut graduations and characters, and as a protective coating and permanent finish.

In the accompanying sheets of drawings, wherein I have shown my invention applied to a scale, Figure 1 is a top plan view of the scale with parts removed; Fig. 2 is an enlarged transverse sectional view, sub- Speeification of Letters Patent.

Patented July 30, 1918.

Serial No. 769,781.

stantially along the line 22 of Fig. 1, parts on the interior of the ruler body being omitted; Fig. 3 is a bottom view of an end por tion of the scale; Figs. at and 5 are transverse sectional views on a slightly enlarged scale, substantially along the line H and 2-2, respectively, Fig. 4 showing the interior parts not shown in Fig. 2; and Fig. (3 is an enlarged longitudinal sectional view of one end of the scale substantially along the line (3-6 of Fig. 1.

The scale is provided with a body which is formed into tubular shape from a thin strip of sheet metal, and, except for certain improvements to be described, which have been rendered in the construction of the body, the latter is of the same shape and form as the ruler body shown in my prior application, previously referred to. The body includes a flat top portion a, and bevcled or inclined portions a which extend from shoulders or ofl'scts a along the edges of the portion a to, the edges of the body. The bottom of the ruler body is formed by bending side portions a of the strip inwardly at acute angles to the portions a, those portions a extending inwardly to substantially the center plane of the body. The edge portions of the strip are bent upwardly into the interior of the ruler body and extend between the top and bottom walls so as to constitute an integral internal bracing rib. The side edges of the body are formed by the bending process straight and parallel, and the edges are slightly rounded and quite thin, as will be seen from Fig. 2. As in my prior construction, the two parts a of the bottom wall of the ruler body are mechanically fastened together at intervals, the mechanical fastening means consisting of pairs of concentric bushings which are arranged along the ccnter line of the ruler body, the central bracing rib a. being notched or cut away at the proper points to accommodate the bushings. As will be ob served, each of these pairs or sets of bushings includes an outer bushing 6 into which portions of both parts a of the bottom wall are upwardly bent, and an inner bushing b which is driven tightly in place from the lower side of the ruler body. Not only do 105 these bushings serveto mechanically fasten together the adjacent parts of the lower side of the ruler body, but by using inner parts of the ruler body,

v edges bushings whieh are threaded on the interior, said bushings constitute very effective anchorages for screws 0 which secure to the top of the ruler body,

adapt the ruler for use with universal draftessential, as celluloid cannot be cemented to ing machines.

One of the nnportant features of the present construction residesin an interlock i'or the edge portions of the strip which form the inner bracing rib a In my prior construction shown in the application pre viously referred to, the edge portions of the strip are bent upwardly from the bottom wall, side by side, to the top wall and are not interlocked.

In the present construction, the edge portions extend between the top and bottom walls, but each edge portion is doubled back upon itself so as to form trough shaped or U-shaped folds a and a, and the interlock is formed'by' inserting one folded part a into the other. These folded parts have a certain degree of spring, and are so formed that when one is inserted within the other, the two interlocking portions grip each other tightly, with the result that the portions as of the bottom wall are united or held together from one end of the ruler body to the other, and this interlocking assists the bushings in holding together the.

and particularly, it overcomes all tendency for lateral spreading or springing of the portions of the bottom wall located between the sets of b'ush-' ings, and thus maintains the outer working in true parallelism.

It will be observed the tubular body is closed at each end by bending the ends a of the portions of forming the bottom of the ruler body upwardly on a curve which extends from the bottom of the scale to the lower side of the top portion a, and by look ing the upwardly curved part to the portion a by bendingia lip-like extension a formed on the end of the portion ca downwardly {and inwardly over the end of the curved portion M. "The edges of the curved portion a and of thebeveled portions 60 fit closely together, and are curved or rounded, asshown at a inFig.1. j

This construction forms not only a very effective closure without the necessity for clo'singinserts' or end plugs,-such as are utilized in the construction shown in my priorjapplication, but the rounded ends and edges thus formed render. the scale more desirable in many respects. V

A further very important improvement and feature of my invention embodied in the present construction resides in the finish of v therulerbody,and the manner of applying graduations ineasily readable form.

In my prior construct1on', the graduations and characters of the scale were cut into celluloid in the form ofstrips whichI dischuck plates cl which;

covered after, much experimenting could be cemented to the metal ruler body, if the latter were first provided with a strongly adhering coating of material, such as baked enamel, the intermediate coating being quite the surface of metal.

By my present invention, I am enabled'to dispense w1th the cemented strips, and secure a finished ruler which is far more satisfactory, both from manufacturing and .commercial standpomts.

Inaccordance with my present invention,

the graduations and characters are cut directly into a coating 6' which preferably, although not necessarily, covers the entire outer surface of the ruler body. In order that a coating which is applied to the ruler body may serve as the medium forxthe cut graduations and characters, this coating must have certain properties not'possessed by coatings such as enamel, with which metal is usually or commonly coated. In the first place, it must adhere very strongly to the metal; it must be hard and smooth and at the same time have a certain degree of flexibility so that .it will not crack'when the ruler body is flexed; its cohesive properties must be such that very fine smooth,

clean clear linescanbecut therein,.and, it must be durable and'be able to withstand blows and rough usage generally without chipping or breaking. o

The coating which I provide on the ruler, body consists of pyroxylin which I find can be applied in liquid-form evenly to the-ruler body, and when hardened'answers all the requirements with high efiiciency, and at the same time gives the ruler body a very desirable permanent finish and serves as an admirable metal protecting mediunn It will be observed that the coating 0, because of its strong adherenceto' the metal, and because of its hardness, resembles, an ordinary baked enamel, but it; differs essen tially from enamel in the respect'that it is not brittle, and because fine smooth lines can be cut into the same. It is obvious that a coating of enamel, or any-other material having the brittle characteristic of enamel is quite unsuitable for, my purpose, for the the o I fined as celluloidal. 3 Celluloid," however,

cannot be used for the purpose. described herein, for the reason that it will not adhere I directly to the metal, regardless of-how or in what form it is applied thereto.. J

Preferably, the portions of the coating in which the graduations and characters are out, viz: the portions which cover the beveled parts a of the ruler body are white, so that the graduations and designating characters of the ruler will stand out sharply and be easily readable. The other portions of the coating may, however, by suitable coloring matter, be given any desired color or colors.

Having thus described my invention, what I claim is 1. A tubular ruler body formed from a strip of sheet metal and having top and bottom walls and one or more ruling edges formed by bending side portions of the strip inwardly with respect to an intermediate portion, the edge portions of the strip being bent inwardly to form an internal rib and being interlocked.

2. In combination in a ruler, a tubular ruler body having top and bottom walls, the end portion of one of said walls being bent at an angle toward the other wall, and the latter having at its end an extension which is folded inwardly over the end of said bent portion.

3. In combination in a ruler, a tubular ruler body having top and bottom walls, the end portion of the bottom wall being inclined upwardly to the top wall ,and the latter having at its end an extension which is folded downwardly and inwardly over the end of said upwardly inclined portion.

4. In combination in a ruler, a tubular ruler body formed from a strip of sheet metal and comprising a top wall and. a bottom wall, the latter being formed by bending the side portions of the strip inwardly with respect to the part forming the top wall, the ends of said inwardly bent portions forming the bottom wall being bent upwardly to the top wall, the latter having at its end an extension which is folded downwardly and inwardly over said upwardly bent parts so as to lock the same in place.

5. A ruler comprising a metal body provided with a hard strongly adhering coating whose cohesive properties are such that fine smooth lines and cha 'acters may be cut in the coating.

6. A ruler comprising a metal body having a strong adhering celluloidal coating in which graduations are cut.

7. A ruler comprising a metal body having a strongly adhering coating of pyroxylin bearing cut graduations.

8. A hollow ruler body formed from a strip of sheet metal, the edge portions of the strip being interlocked on the interior of the body and forming an internal rib extending from one side of the body to the other.

9. A ruler, comprising a metal body, provided with a hard, strongly adhering coating completely enveloping 'the body and having cohesive properties such that fine smooth gradnations may be cut therein.

10. A ruler, comprising a metal body, provided with a hard, strongly adhering and permanently positioned coating enveloping the body, and having cohesive properties such that fine smooth graduations may be cut therein.

11. A ruler, comprising a hollow body having top and bottom walls, the end portion of one of said walls being inclined at an angle toward the other wall, and the latter having at its end a portion which is folded over the end of said inclined portion.

12. A ruler, comprising a metal ruler body completely enveloped in a hard closely adhering medium bearing cut graduations, said medium having cohesive characteristics such that fine gradnations and characters may be cut therein.

13. A. ruler comprising a metal body completely enveloped in a permanently positioned hard covering in which graduations are cut, said covering having cohesive properties which permit fine, smooth, legible lines to be cut therein.

14. A ruler comprising a metal body ontirely surrounded by a covering of pyroxylin bearing cut graduations, said covering being held by the body against substantial shrinkage in any direction.

In testimony whereof, I hereunto aflix my signature in the presence of two witnesses.

CHARLES H. LITTLE.

WVitnesses L. I. PORTER, A. F. KwIs.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

